The invention relates to an apparatus and a method for the cleaning, especially the degreasing of electrically conductive material, as for example metal and/or ceramic lathe turnings and/or grinding sludges, under vacuum conditions in accordance with Patent.
In the machining or grinding of workpieces, large amounts of chips or sludges are produced, which due to the process that produced them are wet with emulsions and oils. The oil or emulsion is necessary for the machining or grinding operation; these fluids serve to cool the workpiece and carry away the chips and sludges. These chips are separated from the fluids in the filters of the machine tools. The liquid itself remains in the machine tool, while the sludges and chips have to be removed from the filters. Due to the great surface area of the chips, they are accompanied by large amounts of lubricant and coolant. To reduce these fluid losses chips in the state of the art are centrifuged or pressed. The fluid is recycled, while the residue remaining has to be disposed of. The disposal of these chips and sludges presents considerable difficulty because they are environmentally intolerable.
Due to the contamination of the chips and sludges with the mineral oils, esters, glycerins, emulsifiers, phosphorous additives or additives containing heavy metals, and other such, these materials cannot be directly fed into a metallurgical melting process, for example. Another impediment is the low bulk density of the chips. For a problem-free disposal, decontamination and a thorough compaction of the chips and/or sludges would have to be performed. In the known cleaning processes the degreasing is performed by washing, pressing or centrifugation. In thermal processes the heat has heretofore been applied by indirect heating, inductive heating or resistance heating, or from fired heat sources.